XLV. (247) Having given these commandments about every description of sacrifice in its turn, namely, about the burnt offering, and the sacrifice for preservation, and the sin-offering, he adds another kind of offering common to all the three, in order to show that they are friendly and connected with one another; and this combination of them all is called the great vow; (248) and why it received this appellation we must now proceed to say. When any persons offer first fruits from any portion of their possessions, wheat, or barley, or oil, or wine, or the best of their fruits, or the firstborn males of their flocks and herds, they do so actually dedicating those first fruits which proceed from what is clean, but paying a price as the value of what is unclean; and when they have no longer any materials left in which they can display their piety, they then consecrate and offer up themselves, displaying an unspeakable holiness, and a most superabundant excess of a God-loving disposition, on which account such a dedication is fitly called the great vow; for every man is his own greatest and most valuable possession, and this even he now gives up and abandons. (249) And when a man has vowed this vow the law gives him the following command; first of all, to touch no unmixed wine, nor any wine that is made of the grape, nor to drink any other strong drink whatever, to the destruction of his reason, considering that during this period his reason also is dedicated to God; for all which could tend to drunkenness is forbidden to those of the priests who are employed in the sacred ministrations, they being commanded to quench their thirst with water; (250) in the second place they are commanded not to show their heads, giving thus a visible sign to all who see them that they are not debasing the pure coinage of their vow; thirdly, they are commanded to keep their body pure and undefiled, so as not even to approach their parents if they are dead, nor their brothers; piety overcoming the natural good will and affection towards their relations and dearest friends, and it is both honourable and expedient that piety should at all times prevail.